| 1 | Family Tree Corporation | Lakewood, CO 80228 | Oil & Gas Operator | Feb 2013 |
| 2 | Fancher Oil LLC | Greenwood, CO 80111 | Oil & Gas Operator | Nov 2006 |
| 3 | Faulconer Vernon E Inc | Tyler, TX 75711 | Oil & Gas Operator | Jul 2025 |
| 4 | FDL Operating, LLC | Judson, TX 75660 | Oil & Gas Operator | Oct 2025 |
| 5 | Federated Oil & Gas Properties | Traverse City, MI 49685 | Gas Operator | Mar 2014 |
| 6 | Felmont Oil Corporation | Walnut Creek, CA 94596-3568 | Oil & Gas Operator | Feb 1990 |
| 7 | Ferguson Oil Company Inc | | Oil & Gas Operator | Apr 1994 |
| 8 | Fina Oil And Chemical Company | Dallas, TX 75221 | Oil & Gas Operator | May 2019 |
| 9 | First Energy Corporation | | Oil & Gas Operator | Jun 1993 |
| 10 | First Sourcenergy Wyoming Inc | Gillette, WY 82718 | Gas Operator | Jul 2003 |
| 11 | Flag-Redfern Oil Company | Oklahoma City, OK 73125 | Oil & Gas Operator | Jul 2002 |
| 12 | Flahive Oil & Gas LLC | Golden, CO 80401 | Oil Operator | Oct 1995 |
| 13 | Florida Gas Exploration Co | | Oil & Gas Operator | Feb 1985 |
| 14 | Flying J Oil & Gas Inc | North Salt Lake, UT 84054 | Oil & Gas Operator | Dec 2009 |
| 15 | Forcenergy Inc | Miami, FL 33129 | Oil & Gas Operator | Mar 2015 |
| 16 | Foree R L | Dallas, TX 75225 | Oil & Gas Operator | Aug 2001 |
| 17 | Forest Oil Permian Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 18 | Forestar Petroleum Corporation | Denver, CO 80202 | Oil & Gas Operator | May 2017 |
| 19 | Frank Louis L | Kingsville, TX 78364 | Oil & Gas Operator | Aug 2003 |
| 20 | Frickey Investment MGT Co LLC | Lakewood, CO 80215 | Oil & Gas Operator | Aug 2025 |
| 21 | Fuel Resources Development Co | Denver, CO 80202 | Oil & Gas Operator | Feb 1994 |